Low Noise Road Surfacing (LNRS) Materials

To improve the quality of life, we have been striving to develop new low noise road surfacing (LNRS) materials for use in Hong Kong. In 2021, we engaged the Hong Kong Polytechnic University to study the use of a more durable LNRS material suitable for local roads in Hong Kong called "6mm Highly Modified Stone Mastic Asphalt"(HMSMA6), which is made of fine-grained gap-graded bituminous mixtures.

In the laboratory, this new material demonstrates superior performance in rutting resistance compared to the preceding generation of LNRS. Moreover, following the encouraging laboratory test results, we have successfully completed a site trial program for this new material on about 20 local roads from 2023 to 2024. In addition to its superior engineering performance, its smooth and optimized surface texture provides a noise reducing property, which alleviates traffic noise impact and improves riding comfort for road users.

We updated Guidance Notes RD/GN/011E and related documents for the full implementation of this new generation of LNRS in April 2025.